Mechanism and Evolution Control of Wide Coal Pillar Bursts in Multithick Key Strata
Coal mine pillar burst frequently occurs in Western China, which seriously restricts safe production. This paper takes the 35 m coal pillar of the 3102 working face of MKQ coal mine as the engineering background. The mechanism and evolution control of pillar bursts in multithick key strata are studi...
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| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | English |
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Wiley
2021-01-01
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| Series: | Shock and Vibration |
| Online Access: | http://dx.doi.org/10.1155/2021/4696619 |
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| author | Wenhao Guo Anye Cao Chengchun Xue Yang Hu Songwei Wang Qian Zhao |
| author_facet | Wenhao Guo Anye Cao Chengchun Xue Yang Hu Songwei Wang Qian Zhao |
| author_sort | Wenhao Guo |
| collection | DOAJ |
| description | Coal mine pillar burst frequently occurs in Western China, which seriously restricts safe production. This paper takes the 35 m coal pillar of the 3102 working face of MKQ coal mine as the engineering background. The mechanism and evolution control of pillar bursts in multithick key strata are studied using field investigation, theoretical analysis, and numerical simulation. The mechanism of dynamic and static stress-induced pillar bursts was revealed combining the “O-X” broken features for key strata and numerical simulation of pillar stress evolution. A prevention scheme is put forward for strata presplit blasting and adjusting coal pillar width to minimize the dynamic and static stresses. The results demonstrate the following. (1) In the multithick strata, the first and second near-field subkey strata have perpendicular “O-X” broken features, whereas the third far-field subkey has parallel “O-X” broken features. The working face has three kinds of periodic weighting phenomena: long, medium, and short. (2) The simulated vertical stress curve of 35 m coal pillar goes through three states: two-peak, asymmetric trapezoidal and symmetrical trapezoidal shape with the different advancing position of working face. The stress concentration is extensively promoting a high-risk area for rock burst. (3) The coal pillar burst was induced by the superposition of energy released by the key strata breaking and the elastic energy accumulated in the wide coal pillar. (4) The monitoring data showed that the long, medium, and short periodic weighting steps of multithick key strata are 141.6 m, 43.2–49.6 m, and 17.6–27.2 m, respectively. The microseismic events energy, frequency, and stress of hydraulic support increment are the highest during the long periodic weighting, and the spatial distribution of microseismic events coincides with the stress concentration area. The theoretical analysis is confirmed with the field practice. |
| format | Article |
| id | doaj-art-5f9875cd70e94dc7b3372b982c48204b |
| institution | Kabale University |
| issn | 1070-9622 1875-9203 |
| language | English |
| publishDate | 2021-01-01 |
| publisher | Wiley |
| record_format | Article |
| series | Shock and Vibration |
| spelling | doaj-art-5f9875cd70e94dc7b3372b982c48204b2025-02-03T06:12:06ZengWileyShock and Vibration1070-96221875-92032021-01-01202110.1155/2021/46966194696619Mechanism and Evolution Control of Wide Coal Pillar Bursts in Multithick Key StrataWenhao Guo0Anye Cao1Chengchun Xue2Yang Hu3Songwei Wang4Qian Zhao5School of Mines, China University of Mining and Technology, Xuzhou, Jiangsu 221116, ChinaSchool of Mines, China University of Mining and Technology, Xuzhou, Jiangsu 221116, ChinaSchool of Mines, China University of Mining and Technology, Xuzhou, Jiangsu 221116, ChinaSchool of Mines, China University of Mining and Technology, Xuzhou, Jiangsu 221116, ChinaSchool of Mines, China University of Mining and Technology, Xuzhou, Jiangsu 221116, ChinaMenkeqing Coal Mine, Zhongtian Hechuang Energy Co. Ltd, Ordos 017000, ChinaCoal mine pillar burst frequently occurs in Western China, which seriously restricts safe production. This paper takes the 35 m coal pillar of the 3102 working face of MKQ coal mine as the engineering background. The mechanism and evolution control of pillar bursts in multithick key strata are studied using field investigation, theoretical analysis, and numerical simulation. The mechanism of dynamic and static stress-induced pillar bursts was revealed combining the “O-X” broken features for key strata and numerical simulation of pillar stress evolution. A prevention scheme is put forward for strata presplit blasting and adjusting coal pillar width to minimize the dynamic and static stresses. The results demonstrate the following. (1) In the multithick strata, the first and second near-field subkey strata have perpendicular “O-X” broken features, whereas the third far-field subkey has parallel “O-X” broken features. The working face has three kinds of periodic weighting phenomena: long, medium, and short. (2) The simulated vertical stress curve of 35 m coal pillar goes through three states: two-peak, asymmetric trapezoidal and symmetrical trapezoidal shape with the different advancing position of working face. The stress concentration is extensively promoting a high-risk area for rock burst. (3) The coal pillar burst was induced by the superposition of energy released by the key strata breaking and the elastic energy accumulated in the wide coal pillar. (4) The monitoring data showed that the long, medium, and short periodic weighting steps of multithick key strata are 141.6 m, 43.2–49.6 m, and 17.6–27.2 m, respectively. The microseismic events energy, frequency, and stress of hydraulic support increment are the highest during the long periodic weighting, and the spatial distribution of microseismic events coincides with the stress concentration area. The theoretical analysis is confirmed with the field practice.http://dx.doi.org/10.1155/2021/4696619 |
| spellingShingle | Wenhao Guo Anye Cao Chengchun Xue Yang Hu Songwei Wang Qian Zhao Mechanism and Evolution Control of Wide Coal Pillar Bursts in Multithick Key Strata Shock and Vibration |
| title | Mechanism and Evolution Control of Wide Coal Pillar Bursts in Multithick Key Strata |
| title_full | Mechanism and Evolution Control of Wide Coal Pillar Bursts in Multithick Key Strata |
| title_fullStr | Mechanism and Evolution Control of Wide Coal Pillar Bursts in Multithick Key Strata |
| title_full_unstemmed | Mechanism and Evolution Control of Wide Coal Pillar Bursts in Multithick Key Strata |
| title_short | Mechanism and Evolution Control of Wide Coal Pillar Bursts in Multithick Key Strata |
| title_sort | mechanism and evolution control of wide coal pillar bursts in multithick key strata |
| url | http://dx.doi.org/10.1155/2021/4696619 |
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